GitLab Documentation guidelines

GitLab's documentation is intended as the single source of truth (SSOT) for information about how to configure, use, and troubleshoot GitLab. The documentation contains use cases and usage instructions for every GitLab feature, organized by product area and subject. This includes topics and workflows that span multiple GitLab features, and the use of GitLab with other applications.

In addition to this page, the following resources can help you craft and contribute to documentation:

Style Guide - What belongs in the docs, language guidelines, Markdown standards to follow, links, and more.
Structure and template - Learn the typical parts of a doc page and how to write each one.
Documentation process.
Markdown Guide - A reference for all Markdown syntax supported by GitLab.
Site architecture - How https://docs.gitlab.com is built.
Documentation for feature flags - How to write and update documentation for GitLab features deployed behind feature flags.

Source files and rendered web locations

Documentation for GitLab, GitLab Runner, Omnibus GitLab, and Charts is published to https://docs.gitlab.com. Documentation for GitLab is also published within the application at /help on the domain of the GitLab instance. At /help, only help for your current edition and version is included. Help for other versions is available at https://docs.gitlab.com/archives/.

The source of the documentation exists within the codebase of each GitLab application in the following repository locations:

Project	Path
GitLab	`/doc`
GitLab Runner	`/docs`
Omnibus GitLab	`/doc`
Charts	`/doc`

Documentation issues and merge requests are part of their respective repositories and all have the label Documentation.

Branch naming

The CI pipeline for the main GitLab project is configured to automatically run only the jobs that match the type of contribution. If your contribution contains only documentation changes, then only documentation-related jobs will be run, and the pipeline will complete much faster than a code contribution.

If you are submitting documentation-only changes to Runner, Omnibus, or Charts, the fast pipeline is not determined automatically. Instead, create branches for docs-only merge requests using the following guide:

Branch name	Valid example
Starting with `docs/`	`docs/update-api-issues`
Starting with `docs-`	`docs-update-api-issues`
Ending in `-docs`	`123-update-api-issues-docs`

Contributing to docs

Contributions to GitLab docs are welcome from the entire GitLab community.

To ensure that GitLab docs are current, there are special processes and responsibilities for all feature changes, that is development work that impacts the appearance, usage, or administration of a feature.

However, anyone can contribute documentation improvements that are not associated with a feature change. For example, adding a new doc on how to accomplish a use case that's already possible with GitLab or with third-party tools and GitLab.

Markdown and styles

GitLab docs uses GitLab Kramdown as its Markdown rendering engine. See the GitLab Markdown Guide for a complete Kramdown reference.

Adhere to the Documentation Style Guide. If a style standard is missing, you are welcome to suggest one via a merge request.

Folder structure and files

See the Structure section of the Documentation Style Guide.

Metadata

To provide additional directives or useful information, we add metadata in YAML format to the beginning of each product documentation page (YAML front matter). All values are treated as strings and are only used for the docs website.

Stage and group metadata

Each page should ideally have metadata related to the stage and group it belongs to, as well as an information block as described below:

stage: The Stage to which the majority of the page's content belongs.
group: The Group to which the majority of the page's content belongs.

info: The following line, which provides direction to contributors regarding how to contact the Technical Writer associated with the page's Stage and Group:

To determine the technical writer assigned to the Stage/Group
associated with this page, see
https://about.gitlab.com/handbook/engineering/ux/technical-writing/#designated-technical-writers

For example, the following metadata would be at the beginning of a product documentation page whose content is primarily associated with the Audit Events feature:

---
stage: Monitor
group: APM
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#designated-technical-writers
---

Document type metadata

Originally discussed in this epic, each page should have a metadata tag called type. It can be one or more of the following:

index: It consists mostly of a list of links to other pages. Example page.
concepts: The background or context of a subject. Example page.
howto: Specific use case instructions. Example page.
tutorial: Learn a process/concept by doing. Example page.
reference: A collection of information used as a reference to use a feature or a functionality. Example page.

Redirection metadata

The following metadata should be added when a page is moved to another location:

redirect_to: The relative path and filename (with an .md extension) of the location to which visitors should be redirected for a moved page. Learn more.
disqus_identifier: Identifier for Disqus commenting system. Used to keep comments with a page that's been moved to a new URL. Learn more.

Comments metadata

The docs website has comments (provided by Disqus) enabled by default. In case you want to disable them (for example in index pages), set it to false:

---
comments: false
---

Additional page metadata

Each page can have additional, optional metadata (set in the default.html Nanoc layout), which will be displayed at the top of the page if defined:

reading_time: If you want to add an indication of the approximate reading time of a page, you can set reading_time to true. This uses a simple algorithm to calculate the reading time based on the number of words.

Move or rename a page

Moving or renaming a document is the same as changing its location. This process requires specific steps to ensure that visitors can find the new documentation page, whether they're using /help from a GitLab instance or by visiting https://docs.gitlab.com.

Be sure to assign a technical writer to a page move or rename MR. Technical Writers can help with any questions and can review your change.

To change a document's location, don't remove the old document, but instead replace all of its content with the following:

---
redirect_to: '../path/to/file/index.md'
---

This document was moved to [another location](../path/to/file/index.md).

Replace ../path/to/file/index.md with the relative path to the old document.

The redirect_to variable supports both full and relative URLs; for example:

https://docs.gitlab.com/ee/path/to/file.html
../path/to/file.html
path/to/file.md

The redirect works for https://docs.gitlab.com, and any *.md paths are changed to *.html. The description line following the redirect_to code informs the visitor that the document changed location if the redirect process doesn't complete successfully.

For example, if you move doc/workflow/lfs/index.md to doc/administration/lfs.md, then the steps would be:

Copy doc/workflow/lfs/index.md to doc/administration/lfs.md

Replace the contents of doc/workflow/lfs/index.md with:

---
redirect_to: '../../administration/lfs.md'
---

This document was moved to [another location](../../administration/lfs.md).

Find and replace any occurrences of the old location with the new one. A quick way to find them is to use git grep on the repository you changed the file from:
```
git grep -n "workflow/lfs/lfs_administration"
git grep -n "lfs/lfs_administration"
```
If the document being moved has any Disqus comments on it, follow the steps described in Redirections for pages with Disqus comments.

Things to note:

Since we also use inline documentation, except for the documentation itself, the document might also be referenced in the views of GitLab (app/) which will render when visiting /help, and sometimes in the testing suite (spec/). You must search these paths for references to the doc and update them as well.
The above git grep command will search recursively in the directory you run it in for workflow/lfs/lfs_administration and lfs/lfs_administration and will print the file and the line where this file is mentioned. You may ask why the two greps. Since we use relative paths to link to documentation, sometimes it might be useful to search a path deeper.
The *.md extension is not used when a document is linked to GitLab's built-in help page, which is why we omit it in git grep.
Use the checklist on the "Change documentation location" MR description template.

Redirections for pages with Disqus comments

If the documentation page being relocated already has Disqus comments, we need to preserve the Disqus thread.

Disqus uses an identifier per page, and for https://docs.gitlab.com, the page identifier is configured to be the page URL. Therefore, when we change the document location, we need to preserve the old URL as the same Disqus identifier.

To do that, add to the front matter the variable disqus_identifier, using the old URL as value. For example, let's say we moved the document available under https://docs.gitlab.com/my-old-location/README.html to a new location, https://docs.gitlab.com/my-new-location/index.html.

Into the new document front matter, we add the following information. You must include the file name in the disqus_identifier URL, even if it's index.html or README.html.

---
disqus_identifier: 'https://docs.gitlab.com/my-old-location/README.html'
---

Merge requests for GitLab documentation

Before getting started, make sure you read the introductory section "contributing to docs" above and the documentation workflow.

Use the current merge request description template
Label the MR Documentation (can only be done by people with developer access, for example, GitLab team members)
Assign the correct milestone per note below (can only be done by people with developer access, for example, GitLab team members)

Documentation will be merged if it is an improvement on existing content, represents a good-faith effort to follow the template and style standards, and is believed to be accurate.

Further needs for what would make the doc even better should be immediately addressed in a follow-up merge request or issue.

If the release version you want to add the documentation to has already been frozen or released, use the label ~"Pick into X.Y" to get it merged into the correct release. Avoid picking into a past release as much as you can, as it increases the work of the release managers.

GitLab `/help`

Every GitLab instance includes the documentation, which is available at /help (https://gitlab.example.com/help). For example, https://gitlab.com/help.

The documentation available online on https://docs.gitlab.com is deployed every four hours from the master branch of GitLab, Omnibus, and Runner. Therefore, after a merge request gets merged, it will be available online on the same day. However, it will be shipped (and available on /help) within the milestone assigned to the MR.

For example, let's say your merge request has a milestone set to 11.3, which will be released on 2018-09-22. If it gets merged on 2018-09-15, it will be available online on 2018-09-15, but, as the feature freeze date has passed, if the MR does not have a ~"Pick into 11.3" label, the milestone has to be changed to 11.4 and it will be shipped with all GitLab packages only on 2018-10-22, with GitLab 11.4. Meaning, it will only be available under /help from GitLab 11.4 onward, but available on https://docs.gitlab.com/ on the same day it was merged.

Linking to `/help`

When you're building a new feature, you may need to link the documentation from GitLab, the application. This is normally done in files inside the app/views/ directory with the help of the help_page_path helper method.

In its simplest form, the HAML code to generate a link to the /help page is:

= link_to 'Help page', help_page_path('user/permissions')

The help_page_path contains the path to the document you want to link to with the following conventions:

it is relative to the doc/ directory in the GitLab repository
the .md extension must be omitted
it must not end with a slash (/)

Below are some special cases where should be used depending on the context. You can combine one or more of the following:

Linking to an anchor link. Use anchor as part of the help_page_path method:

= link_to 'Help page', help_page_path('user/permissions', anchor: 'anchor-link')

Opening links in a new tab. This should be the default behavior:

= link_to 'Help page', help_page_path('user/permissions'), target: '_blank'

Using a question icon. Usually used in settings where a long description cannot be used, like near checkboxes. You can basically use any GitLab SVG icon, but prefer the question-o:
```
= link_to sprite_icon('question-o'), help_page_path('user/permissions')
```
Using a button link. Useful in places where text would be out of context with the rest of the page layout:
```
= link_to 'Help page', help_page_path('user/permissions'),  class: 'btn btn-info'
```

Using links inline of some text.

Description to #{link_to 'Help page', help_page_path('user/permissions')}.

Adding a period at the end of the sentence. Useful when you don't want the period to be part of the link:

= succeed '.' do
  Learn more in the
  = link_to 'Help page', help_page_path('user/permissions')

GitLab `/help` tests

Several RSpec tests are run to ensure GitLab documentation renders and works correctly. In particular, that main docs landing page will work correctly from /help. For example, GitLab.com's /help.

Docs site architecture

See the Docs site architecture page to learn how we build and deploy the site at https://docs.gitlab.com and to review all the assets and libraries in use.

Global navigation

See the Global navigation doc for information on how the left-side navigation menu is built and updated.

Previewing the changes live

NOTE: Note: To preview your changes to documentation locally, follow this development guide or these instructions for GDK.

The live preview is currently enabled for the following projects:

If your merge request has docs changes, you can use the manual review-docs-deploy job to deploy the docs review app for your merge request. You will need at least Maintainer permissions to be able to run it.

You must push a branch to those repositories, as it doesn't work for forks.

The review-docs-deploy* job will:

Create a new branch in the gitlab-docs project named after the scheme: docs-preview-$DOCS_GITLAB_REPO_SUFFIX-$CI_MERGE_REQUEST_IID, where DOCS_GITLAB_REPO_SUFFIX is the suffix for each product, e.g, ee for EE, omnibus for Omnibus GitLab, etc, and CI_MERGE_REQUEST_IID is the ID of the respective merge request.
Trigger a cross project pipeline and build the docs site with your changes.

In case the review app URL returns 404, this means that either the site is not yet deployed, or something went wrong with the remote pipeline. Give it a few minutes and it should appear online, otherwise you can check the status of the remote pipeline from the link in the merge request's job output. If the pipeline failed or got stuck, drop a line in the #docs chat channel.

Make sure that you always delete the branch of the merge request you were working on. If you don't, the remote docs branch won't be removed either, and the server where the Review Apps are hosted will eventually be out of disk space.

TIP: Tip: Someone with no merge rights to the GitLab projects (think of forks from contributors) cannot run the manual job. In that case, you can ask someone from the GitLab team who has the permissions to do that for you.

Troubleshooting review apps

In case the review app URL returns 404, follow these steps to debug:

Did you follow the URL from the merge request widget? If yes, then check if the link is the same as the one in the job output.
Did you follow the URL from the job output? If yes, then it means that either the site is not yet deployed or something went wrong with the remote pipeline. Give it a few minutes and it should appear online, otherwise you can check the status of the remote pipeline from the link in the job output. If the pipeline failed or got stuck, drop a line in the #docs chat channel.

Technical aspects

If you want to know the in-depth details, here's what's really happening:

You manually run the review-docs-deploy job in a merge request.
The job runs the scripts/trigger-build script with the docs deploy flag, which in turn:
1. Takes your branch name and applies the following:
  - The docs-preview- prefix is added.
  - The product slug is used to know the project the review app originated from.
  - The number of the merge request is added so that you can know by the gitlab-docs branch name the merge request it originated from.
2. The remote branch is then created if it doesn't exist (meaning you can re-run the manual job as many times as you want and this step will be skipped).
3. A new cross-project pipeline is triggered in the docs project.
4. The preview URL is shown both at the job output and in the merge request widget. You also get the link to the remote pipeline.
In the docs project, the pipeline is created and it skips the test jobs to lower the build time.
Once the docs site is built, the HTML files are uploaded as artifacts.
A specific runner tied only to the docs project, runs the Review App job that downloads the artifacts and uses rsync to transfer the files over to a location where NGINX serves them.

The following GitLab features are used among others:

Testing

For more information on documentation testing, see Documentation testing

Danger Bot

GitLab uses Danger for some elements in code review. For docs changes in merge requests, whenever a change to files under /doc is made, Danger Bot leaves a comment with further instructions about the documentation process. This is configured in the Dangerfile in the GitLab repository under /danger/documentation/.

Automatic screenshot generator

You can now set up an automatic screenshot generator to take and compress screenshots, with the help of a configuration file known as screenshot generator.

Use the tool

To run the tool on an existing screenshot generator, take the following steps:

Set up the GitLab Development Kit (GDK).
Navigate to the subdirectory with your cloned GitLab repository, typically gdk/gitlab.
Make sure that your GDK database is fully migrated: bin/rake db:migrate RAILS_ENV=development.
Install pngquant, see the tool website for more info: pngquant
Run scripts/docs_screenshots.rb spec/docs_screenshots/<name_of_screenshot_generator>.rb <milestone-version>.
Identify the location of the screenshots, based on the gitlab/doc location defined by the it parameter in your script.
Commit the newly created screenshots.

Extending the tool

To add an additional screenshot generator, take the following steps:

Locate the spec/docs_screenshots directory.
Add a new file with a _docs.rb extension.
Be sure to include the following bits in the file:

require 'spec_helper'

RSpec.describe '<What I am taking screenshots of>', :js do
  include DocsScreenshotHelpers # Helper that enables the screenshots taking mechanism

  before do
    page.driver.browser.manage.window.resize_to(1366, 1024) # length and width of the page
  end

In addition, every it block must include the path where the screenshot is saved

 it 'user/packages/container_registry/img/project_image_repositories_list'

Full page screenshots

To take a full page screenshot simply visit the page and perform any expectation on real content (to have capybara wait till the page is ready and not take a white screenshot).

Element screenshot

To have the screenshot focuses few more steps are needed:

find the area: screenshot_area = find('#js-registry-policies')
scroll the area in focus: scroll_to screenshot_area
wait for the content: expect(screenshot_area).to have_content 'Expiration interval'
set the crop area: set_crop_data(screenshot_area, 20)

In particular set_crop_data accepts as arguments: a DOM element and a padding, the padding will be added around the element enlarging the screenshot area.

Live example

Please use spec/docs_screenshots/container_registry_docs.rb as a guide and as an example to create your own scripts.